Twines equilibrium in a finite element dedicated to hexagonal mesh netting

The equilibrium of hexagonal mesh netting is calculated by a finite element method. A triangular element has been devolopped for such hexagonal meshes[1] [2]. The hexagonal mesh is made of three families of twines. The basic hypothesis of the triangular element imposes that the three families of twines be parallel inside the element. The twine tension are calculated to deduce the forces on the vertex of the triangular element. The calculation of twine tension needs the concurent resolution of 6 equations with as many unknowns. In a first step these equations are reduced to 2 with 2 unknowns. Then they are solved by the Newton-Raphson method